Answer:
The answer is
<h2>11.18 cm³</h2>
Explanation:
The volume of a substance when given the density and mass can be found by using the formula

From the question
mass = 123 g
density = 11.3 g/cm³
The volume is

We have the final answer as
<h3>11.18 cm³</h3>
Hope this helps you
The molar mass of
is 86.02 g/mole
.
<h3><u>
Explanation:</u>
</h3>
The molar mass of a chemical compound is represented as the mass of a unit of that compound separated by the number of substances in that unit, measured in moles. The molar mass is a volume, not molecular, the property of a substance.
The molar mass is a percentage of various examples of the compound, which usually change in mass due to the appearance of isotopes.
From the below attached table, the Molar mass of
is 86.0108 g/mol.
Answer: C. ethanol
The enthalpy of combustion is the amount of heat produced when one mole of ethanol undergoes complete combustion at 25 ° C and 1 atmosphere pressure, yielding products also at 25 ° C and 1 atm.
<u>The enthalpy of combustion of the unknown compound is</u>
ΔH = - 320 kJ / 0.25 mol = - 1280 kJ / mol
<u>To choose a probable compound according to this combustion enthalpy, we must evaluate the deviation in relation to the values reported in the literature for the three probable compounds</u> (methane, ethylene and ethanol). The deviation (e%) will be calculated according to the following equation,
e% = ( | ΔHx - ΔH | / ΔHx ) x 100%
where ΔHx is the enthalpy of combustion of the probable compound.
The following table shows the combustion enthalpies of the probable compounds and their deviation in relation to the enthalpy of ΔH = - 1280 kJ / mol
Compound Enthalpy of combustion (kJ/mol) Deviation
Methane - 890.7 43.8%
Ehylene -1411.2 9.3%
Ethanol -1368.6 6.5%
According to the previous table, we can say that the most probable compound is ethanol, since it has the smallest deviation in relation to the experimental enthalpy value of combustion.
Following reaction occurs in the given electrochemical system:

→ Fe +

Thus, under standard conditions
E(0) = E(0) Fe2+/Fe - E(0) Zn2+/Zn
where,

= standard reduction potential of Fe2+/Fe = -0.44 v

= standard reduction potential of Zn2+/Zn = -0.763 v
E(0) = 0.323 v
now, we know that, ΔG(0) =-nFE(0) ............... (1)
Also, Δ

On equating and rearranging equation 1 and 2, we get
K = exp(

)= exp (

) = 8.46 x